Abstract: In urban soft soil strata, constructing underground stations for urban rail transit presents challenges in balancing process adaptability with the dual goals of carbon peaking and carbon neutrality. Traditional open-cut construction methods face issues such as high material consumption, long construction periods, difficulty in controlling carbon emissions, and significant impacts on surrounding environments. To explore a greener and more efficient construction solution, the authors investigate the Caozhuang station of the Jiaxing-Fengnan urban rail transit, applying and innovating the continuous caisson construction method. By integrating a digital twin monitoring platform with an integrated digital pressure-sinking system, the sinking sequence of caissons and the construction process of internal middle and top slabs are dynamically adjusted. During the sinking process, soil plug height is regulated in real time, surrounding settlement is controlled, caisson sinking accuracy is precisely maintained, and construction efficiency is improved. Simultaneously, integrated station and tunnel construction is accelerated. The project demonstrates the following practical innovations: (1) Compared with the open-cut excavation method, the caisson method reduces earthwork by 7% and project costs by 8%. (2) Material consumption and carbon emissions are significantly reduced—concrete usage decreases by 16% and steel reinforcement by 20%, resulting in a total carbon emission reduction of 3 831 t, equivalent to eliminating the combustion of 1 945 t of anthracite coal.

Key words: urban railway underground station, continuous caisson, intelligent monitoring and early warning, frictional resistance reduction